Okay I have to say, the intro is hand-down my favorite so far in this Jam and it's not even close, it was hilarious and cutesy and meme-y and all that, definitely made me really hooked immediately!
And then this stuff keeps on being great, all the way to the "reveal", I lost it with the flashback of catmom saying that catdad is always the cutest, genuinely incredible stuff hahaha. Even the transitions between bosses, the loading screens, the music, etc., everything is *REALLY* nicely done and I loved it.
Gameplay wise, I found the dive/submerge mechanic really cool. There wasn't any boss attack that I felt like it wasn't obvious, it was very easy to tell whether I should be above water or below water and it was really interesting to use that to dodge stuff. I find this even more particularly interesting because our game has a similar premise (boss in the middle, rotate around him), and while we did consider having a "multiple rings" thing going on to give us more freedom in designing boss abilities, it never crossed our minds to have something like your submerge/dive, I genuinely think it is genius, and it was perfectly integrated into the gameplay.
Really strong entry, great job!